If

here we have to find the double derivative, so to find double derivative we will just differentiate the first derivative once again with a similar method.

Theorem: y and x are given in a different variable that is θ . We can find by finding and and then dividing them to get the required thing.

=

………..(1)

= a(1-cosθ ) ……….(2)

Dividing (1) and (2), we get

=

=

= -cot (θ/2)

⇒ To find f’’ we will differentiate f’ with θ and then divide with equation (2).

=

=

=